Display sheet material and method

ABSTRACT

A display sheet material is provided which generates interference fringe patterns which appear to move to an observer upon relative movement of the sheet and the observer. In one form, lenticular formations or parallel printed lines on respective surfaces of different transparent sheets generate fringe patterns. The sheets are secured together in a manner to permit some degree of movement between portions of both sheets to permit variation in the shape and configuration of the fringe patterns.

United States Patent [1 1 Lemelson 1 DISPLAY SHEET MATERIAL AND METHOD[76] Inventor: Jerome H. Lemelson, 85 Rictor St.,

Metuchen, NJ. 08840 22 Filed: Mar. 27, 1972 211 Appl. No.: 233,570

Related U.S. Application Data [63] Continuation-impart of Ser. No.849,117, Aug. 11,

1969, Pat. N0. 3,684,614.

[52] U.S. Cl. 350/164; 350/106; 40/106.51;

40/136; 40/137; 428/29; 428/34; 428/203 [51] Int. Cl 34 1/06 [58] Fieldof Search 161/1, 2, 3.5, 116,14,

[56] References Cited UNITED STATES PATENTS 2,917,854 12/1959 Swarbrick.1 40/106.51 2,951,419 9/1960 Leme1son...... 350/106 2,982,033 5/1961Bingham 40/1065] 3,003,599 10/1961 Rubissow 161/116 1 1 May 20, 19753,155,764 11/1964 Gill, Jr. 350/106 3,250,173 5/1966Henry................ 161/2 3,264,164 8/1966 .lerothe et al.. 161/1 163,312,006 4/1967 Rowland 350/106 3,340,669 9/1967 Farquharson 156/1563,357,772 12/1967 Rowland 161/116 3,523,055 8/1970 Lemelson 156/1563,538,632 11/1970 Anderson 40/137 3,589,045 6/1971 Rakowski 40/1373,683,419 8/1972 Lewis 40/106.5l

Primary Examiner-George F. Lesmes Assistant Examiner-Stanley S.Silverman [57] ABSTRACT A display sheet material is provided whichgenerates interference fringe patterns which appear to move to anobserver upon relative movement of the sheet and the observer. In oneform, lenticular formations or parallel printed lines on respectivesurfaces of different transparent sheets generate fringe patterns. Thesheets are secured together in a manner to permit some degree ofmovement between portions of both sheets to permit variation in theshape and configuration of the fringe patterns.

10 Claims, 8 Drawing Figures DISPLAY SHEET MATERIAL AND METHOD RELATEDAPPLICATIONS This is a continuation in part of application Ser. No.849,l l7 filed Au'g. l l, 1969 for Display and Manufacturing Apparatusnow U.S. Pat. No. 3,684,6l4.

SUMMARY OF THE INVENTION This invention relates to improvements indisplay sheet material, preferably flexible translucent plastic sheetcapable of generating interference fringe patterns which appear to moveor change configuration as the sheet is moved or deformed.

It is a primary object of this invention to provide a new and improveddisplay sheet material having optical effects which are attentiongetting and pleasing to observe.

Another object is to provide a display sheet material in which isgenerated interference fringe patterns which not only may be made toshift position or move as the sheet is handled but will also change inconfiguration.

Another object is to provide a display material which is low in cost andmay be used for a component of various products.

Another object is to provide a display material containing lenticularformations therein for generating a variety of optical effects includinginterference patterns, which formations are disposed facing each otherLII within the sheet and are therefore protected from damage orcontamination.

Another object is to provide a display material capable of generatingchanging optical effects, which material may also be utilized to heatinsulate and protect by shock absorption, an article with which it isassembled.

Another object is to provide an apparatus and method for forming indiciawithin a transparent plastic sheet which is deliniated from a backgroundof interference patterns by exhibiting a lack or variation in suchinterference patterns.

With thee above and such other objects in view as may hereafter morefully appear, the invention consists of the novel constructions,combinations and arrangements of parts as will be more fully describedand illustrated in the accompanying drawings, but it is to be understoodthat changes, variations and modifications may be resorted to which fallwithin the scope of the invention as claimed.

IN THE DRAWINGS:

FIG. I is an end cross-sectional view of a fragment of a first form ofdisplay sheet material formed of two abutted transparent, embossedsheets;

FIG. 2 is an end view in cross section of a fragment of a display sheetmaterial containing portions of two embossed sheets which arespaced-separated from each other;

FIG. 3 is an end cross-sectional view of a composite display sheetmaterial having printed grid patterns for generating interferenceeffects;

FIG. 4 is an end cross-sectional view of a portion of a display sheetmaterial having lenticular surface formations which face each other;

FIG. 5 shows a fragment of the material of FIG. 4 in a flat condition;

FIG. 6 shows the fragment of FIG. 5 deformed;

FIG. 7 is an end cross-sectional view of a portion of sheet materialcapable of producing interference optical effects which appear to changein configuration and move when the sheet is deformed, the sheet materialbeing made of a lamination of lenticular material and printed material;and

FIG. 8 is an end cross-sectional view of a portion of display sheetmaterial of the type shown in FIG. 1 and embossing means therefore forchanging the content of the image changing or interference patterndisplay.

FIG. I is an end cross sectional view of a display material 10 made oftwo sheets 11 and I5 0f translucent material such as transparent plastichaving flat contacting surfaces 12 and 16 and respective outer surfacesI3 and 17 in which are formed respective lenticular formations l4 and18. The lenticular formations l4 and 18 are respective parallel arraysof oblong lenses such as semi-cylindrical parallel ribs embossed ormolded in the respective faces 13 and 17 of the sheets. I havediscovered that if the parallel oblong lens formations in one sheet areangulated between about 3 and 25 to the parallel lens formation in theother sheet, interference bands will develop which are observablethrough the composite material 10 from either surface thereof whichbands will vary in thickness depending on the angle between the lensformations. Furthermore, the interference bands will appear to move toan observer as the angle between the line of sight and the observer andthe surface of the composite material 10 changes further, the degree andrelative velocity of movement of the interference bands is a function ofangle between parallel lens formations which velocity and degreeincreases as the angle increases until the interference effectsubstantially disappears at an angle of between 20 and 25.

If the materials of which two sheets 11 and 15 are made is a flexibleplastic such as plasticized polyvinyl chloride, and the total thicknessof the composite sheet 10 is less than about 60 mils, and preferablyunder 25 mils, the sheet may be easily bent or flexed as applied to asubstrate or during its handling. and will generate very eyecatching, ifnot startling, optical effects. The two sheets II and 15 may be solventor adhesive bonded or welded together along their entire flat sides oras described hereafter.

In FIG. 2 is shown a composite sheet material 20 made of two sheets 21and 25 of flexible material of the type defined in FIG. 1 or asotherwise defined hereafter, which sheets are bonded or welded togetheronly along space-separated spot or band-like areas or lines 29permitting portions of the sheets between the joined portions to becomeslightly separated and/or shift with respect to each other as thecomposite assembly 20 is deformed as it is handled, used or otherwisemoved. The volume V between the sheets 21 and 25 may be an air space ofsuch thickness as to permit certain portions of the two sheets tocontact each other during the handling, bending or folding of thematerial 20 while other areas adjacent to the contacting areas remainout of contact, and/or to permit variation in the separation distancesbetween the flat faces 22 and 26 of the sheets across the non-bondedportions so as to generate slight interference effects which vary inshape, size and degree of movement as the material is handled orotherwise deformed.

While the lens formations 24 and 28 in the outer faces 23 and 27 of thetwo sheets may comprise oblong semi-cylindrical formations. they mayalso be formed in any other configuration which will generate fringepatterns which will be affected as described, by the separation andrelative shifting of those portions of the two sheets which are notjoined. Semi-spherical or otherwise formed configurations will alsoserve to generate 7 suitable fringe patterns which vary as described.

In a modified form of the embodiment of FIG. 2 it is noted that gasunder pressure slightly above atmospheric perhaps a pound or two or lessmay be entrapped between the sheets in the volumes V to expand the sheetportion thereof and maintain them slightly apart.

It is noted that fringe pattern effects which change, as described, mayalso be generated in the material if the sheets are joined together withsurfaces 26 and 27 containing lenticular formations 24 and 28 facingeach other.

In FIG. 3 is shown another form of the invention wherein a compositematerial 30 is made of two sheets 31 and 35 of flexible translucent ortransparent plastic, as described, which are welded together alongspaceseparated spot or band-like areas 39 leaving portions 31a and 35aof the sheets 31 and 35 with their inside faces 32 and 36 which areunjoined and are capable of a slight degree of relative shifting as thesheets are bent or flexed. Printed on the outer faces 33 and 37 of thesheets 31 and 35 are respective indicia 34 and 38 which may compriserespective sets of parallel bands of opaque or translucent coloredprinting material. Various interference effects may be generated whichvary as described, by providing the parallel space separated bands 34 onone face, angulated with respect to those on the other face. The indiciamay also be disposed on the inside faces 32 and 36 of the sheets 31 and35 although the interference effects will not be as prounounced.Depending on the interference effects desired, the indicia arrayscomposed of elements 34 and 38 may comprise opaque or colored paralleltranslucent bands which in the range of 0.005 to 0.050 inches wide whichare angulated between about 3 and to each other. The bands arepreferably equispaced from each other a degree equal to the width ofeach band although their thickness and separation may vary across thecomposite sheet. The printed matter on the opposite faces 33 and 37 ofthe sheets may also comprise spot-like depositions of ink which are ofthe same shape and equi-spaced from each other to produce interferencepatterns which vary in shape and appear to move as the material isflexed in handling or use.

The volumes V shown as existing between those portions of the sheets 31and of FIG. 3 which are disposed between the band-like bonded or weldedinterfacial areas 39 may vary in thickness from substantially slidingcontact between the two sheets which will permit relative shifting ofthe printed bands 34 and 38 on the outer surfaces of the compositematerial 30 as said material is handled and deflected or bent during useto a height which is attained as a result of gas pressurizing saidvolumes to retain the flexible sheet portions of which the compositematerial is made apart from each other as illustrated. If the printedbands or lines 34 and 38 are relatively narrow, say within the range of0.005 and 0.030 inches wide, then interference bands may be generatedwhich will appear to move or shift in pattern as the flexible materialis deflected or bent during use.

If the bands 34 and 38 are relatively wider, in the range of 0015-0060inches and are equally spaced apart with the bands on one face of thecomposite material angulated with respect to those printed on the otherface thereof, and the volume V is greater than the thickness of one ofthe sheets comprising the composite material and preferably greater thanthe total thickness of the two sheets, then various dynamic opticaleffects may be derived which will be eye-catching and striking to anobserver. For example, the so-called picket fence effect" may be derivedwherein the illusion of movement of interference bands is effected to anobserver looking through the composite material and moving relativethereto.

It is further noted that while the structure shown in FIG. 2 illustratesa volume V having a thickness which is about one third of the thicknessof one of the two lenticulated sheets, comprising the compositematerial, said volume may be larger or smaller in thickness thanillustrated depending on the total thickness and stiff ness of the twosheets comprising the composite material, whether or not a gas underpressure is disposed between the two sheets and in accordance with theoptical effects desired. At one extreme, the volume V may be such as topermit both sliding contact between the two faces 22 and 26 of thesheets 21 and 25 and also separation of said faces depending on thephysical deflection or bending of the material, thereby permittingvariable optical effects in interference patterns to be created as thematerial is handled or otherwise deflected.

In FIG. 4 is shown another form of composite material 40 composed ofseparate sheets 41 and 44 of flexible transparent plastic material, eachpreferably in the range of 0003-0030 inches thick and each provided withrespective lenticular formations 43 and 46 formed in surfaces thereofwhich face or abut each other in the laminated assembly shown andcomprising the composite material. The lenticular formations 43 and 46formed in respective facing surfaces 42 and 45 of the sheets 41 and 44may be semi-spherical in shape and offset from each other orsemi-cylindrical in shape and angulated as described with respect toeach other to provide a variety of different interference effectsdepending on the shape, width and degree of offsetting or angulationbetween the lenticular formations in the two sheets.

To secure the two sheets 41 and 42 together, a plurality of weld or bondareas 47 which may be in the shape of spot-like areas or lines runningparallel to or criss crossing each other are provided and aresufficiently spaced from each other to permit the material of the twosheets between each of the bond areas or welds to contact each other orbe separated from each other, as illustrated, to provide an extendedinterfacial volume 48 therebetween and interference effects which willappear to change and become variably irregular depending upon the shapeand deformation or bending of the composite material.

FIGS. 5 and 6 illustrate how the lenticular formations in the sheetportions 41 and 44 of the sheet material of FIG. 4 may shift withrespect to each other as the composite material is deflected or bent. InFIG. 5 the lenticular formations 43 in sheet portion 41 aresubstantially aligned with lenticular formations 46 in sheet portion 44.In FIG. 6, the composite material 40 has been bent or curved about araise such as to cause a slight shifting of the formations in each sheetportion with respect to those of the other sheet portion. As a result.not only will there be a shifting in the interference pattern formed bythe shifting of the lenticular formations but there will also be avariation in the shape of said pattern caused by certain of thelenticular formations of one sheet separating from those of another asillustrated.

In FIG. 7 is shown a modified form of display sheet which is alamination of two sheets 47 and 49. the former having its outer surfaceembossed with semicylindrical or semi-spherical lenticulations 48 andthe latter (49) being provided with indicia P printed on its insidesurface which is bonded to the inside surface of sheet 47 only alongspace separated band or spot like areas between the two so as to provideportions of the composite sheet which may abut or become separated adistance from each other depending on the degree the two sheets aredeflected. If the formations 48 are elongated ribs such assemicylindrical in shape and the indicia P is composed of parallel spaceseparated opaque or transparent colored bands or two or more arrays ofcolored band which are interposed between each other positioned andconfigured to generate image changing or color changing effects. byvariably separating the two sheets as they are deflected in handling,further variations in such image or color changing effects may beproduced as the sheet material composed of the two sheets 47 and 49 isdeflected or deformed such as in handling. For example, portions of theimage being viewed may disappear or change in content due to lateralshifting of the two sheet portions thereof as shown in FIGS. 5 and 6.

In FIG. 8 is shown an apparatus and method for varying the shape andinterference effects formed in a display sheet material constructed inaccordance with the teachings of FIG. 1 although the apparatus may alsobe utilized to provide indicia or design in material of the type shownin FIG. 4.

The lenticular material. denoted 57. is a sheet having lenticularformations 58 in one surface thereof and cooperating lenticularformations 59 in the opposite surface thcreof. The lenticular formations58 and 59 may comprise semi-spherical or semi-cylindrical formationswhich are operable to generate interference patterns in the two sheetswhich appear to move to an observer whose line of sight is shifting withrespect to the sheet material. In order to provide indicia such assymbols, trademarks, letters numbers or other designs in the sheetmaterial 57, certain of the lenticular formations in both surfaces ofsaid sheet are removed by means of an apparatus 50 composed of opposedembossing plates or rolls SI and 54 having raised portions 52 and 55 andrecessed portions 53 and 56. The raised portions 52 and 55 serve tocompress certain portions 60 of the sheet 57 therebetween and if theplates 51 and 54 are properly heated may be used to emboss out thelenticular formations in the outer surfaces of the sheet 57. The areasin which the lenticular formations are embossed out may be of anysuitable configuration and may serve to eliminate the interferenceeffects along said embossed-out areas so as to provide a sheet havinginterference effects defining certain areas thereof and no suchinterference effects comprising other areas thereof which are deliniatedfrom the interference areas by the lack of interference bands or othershapes.

I claim:

l. A composite flexible display sheet material made of a plurality ofthin light transmitting flexible plastic sheets comprising:

first and second sheets defining different strata of said sheetmaterial, means for joining said first and second sheets facewisetogether along a plurality of space-separated portions of said first andsecond sheets with juxtapositioned portions of said sheets between thejoined portions of said sheets being unjoined and capable of some degreeof relative shifting movement with respect to each other when thecomposite sheet material is deformed out of flatness,

each of said first and second sheets containing respective lightdiffracting means which cooperates with the light diffracting means ofthe other sheet in generating optical fringe pattern effects to anobserver looking through said composite sheet material, and operablewhereby, when the sheet material is flexed, said observed fringe patterneffects will appear to the observer to change in shape and to move adegree other than the degree of movement of the display sheet materialduring the flexure thereof.

2. A composite display sheet material in accordance with claim 1 whereinsaid light diffracting means of at least one of said sheet layerscomprises lenticular formations in at least one surface thereof.

3. A composite display sheet material in accordance with claim 1 whereinsaid light diffracting means comprises lenticular formations formed inat least one of the major surfaces of each of said sheet layers.

4. A composite display sheet material in accordance with claim 3 whereinsaid lenticular formation formed in said first and second sheet layerscomprise respective parallel rib formations with the parallel ribformations in one sheet layer being angulated to the rib formationsformed in the other layer to generate interference fringe patterns whichare viewable through said sheet material which fringe patterns vary inshape and positions as said material is flexed.

5. A composite display sheet material in accordance with claim 3 whereinsaid lenticular formations in said first and second sheet layers areclosely spaced short protrusions each defining a respective lightdiffracting lens and the protrusions of one layer are offset a degreefrom the protrusions of the other layer a degree to generate aninterference fringe pattern effect which will vary in shape as the sheetmaterial is flexed.

6. A composite display sheet material in accordance with claim 1 whereinsaid light diffracting means comprises lenticular formations in bothsaid sheets formed in the abutting surfaces of said sheets.

7. A composite display sheet material in accordance with claim 1 whereinsaid light diffracting means comprises rib-like lenticular formations inthe outer surface of one of said sheet layers and printed matter on theinside surface of the other of said sheet layers cooperating with saidlenticular formations to provide a changing optical effect alongabutting portions of the first and second sheet layers.

8. A composite display sheet material in accordance with claim 1 whereinsaid light diffracting means comprises spaced apart printed formationsdisposed on both said sheet layers and separated from each other by thethickness of at least one of said sheet layers.

and second sheet layers are configured and separated from each other soas to permit relative lateral movement of the unjoined portions of thetwo layers as the sheet material is flexed to create changing opticaleffects.

* w a a:

1. A composite flexible display sheet material made of a plurality ofthin light transmitting flexible plastic sheets comprising: first andsecond sheets defining different strata of said sheet material, meansfor joining said first and second sheets facewise together along aplurality of space-separated portions of said first and second sheetswith juxtapositioned portions of said sheets between the joined portionsof said sheets being unjoined and capable of some degree of relativeshifting movement with respect to each other when the composite sheetmaterial is deformed out of flatness, each of said first and secondsheets containing respective light diffracting means which cooperateswith the light diffracting means of the other sheet in generatingoptical fringe pattern effects to an observer looking through saidcomposite sheet material, and operable whereby, when the sheet materialis flexed, said observed fringe pattern effects will appear to theobserver to change in shape and to move a degree other than the degreeof movement of the display sheet material during the flexure thereof. 2.A composite display sheet material in accordance with claim 1 whereinsaid light diffracting means of at least one of said sheet layerscomprises lenticular formations in at least one surface thereof.
 3. Acomposite display sheet material in accordance with claim 1 wherein saidlight diffracting means comprises lenticular formations formed in atleast one of the major surFaces of each of said sheet layers.
 4. Acomposite display sheet material in accordance with claim 3 wherein saidlenticular formation formed in said first and second sheet layerscomprise respective parallel rib formations with the parallel ribformations in one sheet layer being angulated to the rib formationsformed in the other layer to generate interference fringe patterns whichare viewable through said sheet material which fringe patterns vary inshape and positions as said material is flexed.
 5. A composite displaysheet material in accordance with claim 3 wherein said lenticularformations in said first and second sheet layers are closely spacedshort protrusions each defining a respective light diffracting lens andthe protrusions of one layer are offset a degree from the protrusions ofthe other layer a degree to generate an interference fringe patterneffect which will vary in shape as the sheet material is flexed.
 6. Acomposite display sheet material in accordance with claim 1 wherein saidlight diffracting means comprises lenticular formations in both saidsheets formed in the abutting surfaces of said sheets.
 7. A compositedisplay sheet material in accordance with claim 1 wherein said lightdiffracting means comprises rib-like lenticular formations in the outersurface of one of said sheet layers and printed matter on the insidesurface of the other of said sheet layers cooperating with saidlenticular formations to provide a changing optical effect alongabutting portions of the first and second sheet layers.
 8. A compositedisplay sheet material in accordance with claim 1 wherein said lightdiffracting means comprises spaced apart printed formations disposed onboth said sheet layers and separated from each other by the thickness ofat least one of said sheet layers.
 9. A composite display sheet materialin accordance with claim 1 wherein the voids between saidspace-separated portion of said first and second layers of sheetmaterial are gas pressurized.
 10. A composite display sheet material inaccordance with claim 1 wherein the joined portions of said first andsecond sheet layers are configured and separated from each other so asto permit relative lateral movement of the unjoined portions of the twolayers as the sheet material is flexed to create changing opticaleffects.